Disazo dyes and processes of making same.



UNITED STATES PATENT onrroE.

GEOBG KALISCHER, OF MAIN'KUR, NEAR FRANKFORT-O'N-THE-MAIN, GERMAN T,

ASSIGNOR'TO CASSELLA COLOR OOMPAN Y, A CORPORATION OF NEW YORK.

DISAZO DIES AND PROCESSES OF MAKING SAME.

1,079,415. No Drawing.

Specification of Letters I'atent. Application filed February 27,1918; Serial No. 750,943.

PatentedNov.25,1-913.

To all whom, it may concern:

I naphthol.7.sulfo-nic acid Be it known that I, GEoRoKALIsoHER, Ph. D., a subject of the'King of Prussia, and residing at. Waldstrasse 23, Ma-inkur, near Frankfort-on the-Main, Germany, have invented certain new and useful Improve- (in which X represents the nucleus of an amino compound andY hydrogen or any alkyl or aryl' or acidyl group). They contam as first and last com onents molecules of 2.5.aminonaphtholfisnfionic acid or its derivatives, the middle component being any amino compound which allows of subsequent diazotizing.

The new dyestulfspossess excellent ailinity to the cotton fiber. They yield reddish violet to blue dyeings which, treated with p-nitrodiazobenzene, are developed into considerably deeper dyeings of very clear violet, to blue shades whichpossess, besides excel-' lent fastness to washing and light, the valuable property of yielding pure white discharge efi'ects.

The new dyestutl's are prepared by combining the diazo compound of 2.5.aminonaphthol.7.sulfonic acid with an amino compound (such as m-amino-p-cresol-methyl- NHY color. The process of manufacture is illus trated by the following examples:

Example I: The diazocompound prepared in the usual manner from 23.9 kilos 2.5.aminonaphthoL'Lsulfonic acid is introduced into the aqueous solution of 13.7 kilos m-amino-p-cresolmethylether and 14 kilos hydrochloric acid, the solution having been heated to 25 C. By gradually adding acetate of' soda, the free mineral acid is neutralized. After the reaction is complete, the aminoazo dyestufl isfiltered oil and then dissolved by means of 23 kilos soda lye; 6.9 kilos nitrite are added and the solution is poured into an excess of dilute h drochloric acid. The diazotized compound thus. obtained is poured into a cold solution of 31.5 kilos 2.5.phenylaminonaphthol.7.sulfonic acid, kept alkaline with carbonate of soda. The dyestufl is filtered oil and dried. It is a dark powder, easily soluble in water wit-h a violet blue color, dissolving in concentrated sulfuric acid with a bluish green color, and dyes cotton direct violet blue shades, which by an after treatment wlth p-nitrodiazobenzene yield clear blue shades.

sulfuric acid with a blue to bluish green I SO'NV /N=N\/ If the end component 2.5.phenylamino is re laced by 2.5.' aminonaphthol.7.sulfonic aci or 2.5.benzoylaminonaphthol.7.sulfonic acid, dyestuffs result possessing similarv properties, but of somewhat redder shade.

It has the formula aminonaphthol.7.sulfonic acid in the resence of soda. The monazo dyestufl is filtered V ofl', suspended in water and diazotized by the addition of 4:0 kilos hydrochloric acid and 6.9 kilos nitrite. The diazotized compound thus obtained is poured into a solution of 23.9 kilos 2.5.aminonapht-hol7asulfonic acid containing an excess of soda. The dyestuff is precipitated with common salt, filtered oif and dried. The same dyestuff can be prepared in a slightly different way by combining the monazo dyestuti, dissolved in an excess of soda, with the diazo compound obtained from 23.9 kilos 2.5.aminonaphthol.7.su1fonic acid. The dyestufi' (X representing the nucleus of an amino compound, Y meaning a univalent radical) which consists in combining one molecule of diazotized 2.5.aminonaphthoLT.sulfonic acid with one molecule of an amino compound suitable to be further diazotized, then diazo tizing the monoazo dyestufl thus obtained and combining in alkaline solution with one molecule of a 2.5.aminonaphthol.7.sulfonic compound substantially as described.

2. The herein described process of prois a dark powder soluble in water with a violet color, soluble in concentrated sulfuric acid with a blue color, dyeing reddish violet shades which turn a blue violet when treated with p-nitrodiazobenzene.

Having now described my invention and the manner in which it may be carried out, what I claim is:

1. The herein described process of producling disazo dyes having the general fornm a ducing disazo dyes SO Na /NHY sulfuric acid with a blue to,bluish green color, dyeing cotton in reddish violet to blue being a dark 1 owder soluble in water with a violet blue co or, dissolving in concentrated sulfuric acid with abluish green color, dyeing cotton in violet blue shades, which treate with p-nitrodiazobenzene yield clear blue shades fast to washing and light and which can be discharged to a pure white, substantially as described.

g-nitrodiazobein N H CaHs In witness whereof I have hereunto signed my name this 12th day of February 1913, in the presence of two subscribing witnesses.

DR. GEORGi KALISCHER.

\Vitnesses JEAN GRUND, CARL GRUND.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

